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If alpha is the nth root of unity then 1...

If `alpha` is the nth root of unity then `1+2alpha+3alpha^(2)+`............to `n` terms is equal to

A

`(-n)/((1-alpha)^(2))`

B

`(-n)/(1-alpha)`

C

`(-2n)/(1-alpha)`

D

`(-2n)/((1-alpha)^(2))`

Text Solution

Verified by Experts

The correct Answer is:
B
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